Files
open-roms/c64/kernal/tape/tape_normal_sync.s
T
FeralChild64 d489e7bf41 tape routines can now be placed in Mega65 extra ROM space
commit 2f27e29758da1f1ec965588c0712125051a6f71a
Merge: ba722b1 796b62f
Author: FeralChild64 <you@example.com>
Date:   Tue Jan 28 17:34:53 2020 +0100

    Merge branch 'master' into tape_redirect

commit ba722b17e627af7dd067932688de0a3d86423e37
Author: FeralChild64 <you@example.com>
Date:   Tue Jan 28 17:28:19 2020 +0100

    finished Mega65 variant of tape routines

commit 47de685f2e08576504c5e00a5b7cb78498d22e72
Author: FeralChild64 <you@example.com>
Date:   Mon Jan 27 23:06:45 2020 +0100

    compilation fix

commit c3641acec049a7a6b53c35795b1f9e2df212cec2
Author: FeralChild64 <you@example.com>
Date:   Mon Jan 27 22:53:30 2020 +0100

    dependencies fix

commit dfad7a30bde043fa077005624dde1de4b72573b6
Merge: e4b0ec9 e410bc0
Author: FeralChild64 <you@example.com>
Date:   Mon Jan 27 21:25:49 2020 +0100

    Merge branch 'master' into tape_redirect

commit e4b0ec9c85861bde2ce52e0828d3bf895a681e17
Author: FeralChild64 <you@example.com>
Date:   Sat Jan 25 22:25:20 2020 +0100

    initial attempt to move tape code to Mega65 extra ROM
2020-01-28 17:35:42 +01:00

46 lines
755 B
ArmAsm

// #LAYOUT# STD * #TAKE
// #LAYOUT# M65 KERNAL_1 #TAKE
// #LAYOUT# * * #IGNORE
//
// Tape (turbo) helper routine - synchronization handling
//
// .Y should contain start value (either $89 or $09)
// Carry set = failed
#if CONFIG_TAPE_NORMAL
tape_normal_sync:
lda #$06
sta VIC_EXTCOL
// Injest bytes of decreasing values
jsr tape_normal_get_marker_while_sync
bcs tape_normal_sync_fail // branch if end of data marker
jsr tape_normal_get_byte
bcs tape_normal_sync_fail
cpy INBIT // INBIT contains same value as .A
bne tape_normal_sync_fail
dey
and #%01111110
bne tape_normal_sync // branch if not $80 and not $00
clc
rts
tape_normal_sync_fail:
sec
rts
#endif